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</a></div> <!----></nav>  <ul class="sidebar-links"><li><a href="/docs/exam/" aria-current="page" class="sidebar-link">介绍</a></li><li><section class="sidebar-group depth-0"><p class="sidebar-heading open"><span>面试相关</span> <!----></p> <ul class="sidebar-links sidebar-group-items"><li><a href="/docs/exam/resume-ryf.html" class="sidebar-link">如何写一份有效的技术简历？</a></li><li><a href="/docs/exam/2020-interview-ms.html" class="sidebar-link">2020 年前端面试提纲</a></li><li><a href="/docs/exam/html-css.html" class="sidebar-link">HTML&amp;CSS 面试题</a></li><li><a href="/docs/exam/javascript.html" class="sidebar-link">JavaScript 面试题</a></li><li><a href="/docs/exam/vue.html" class="sidebar-link">Vue 面试题</a></li><li><a href="/docs/exam/actual-interview.html" aria-current="page" class="active sidebar-link">开放性题目</a></li><li><a href="/docs/exam/expand.html" class="sidebar-link">前端相关拓展题</a></li><li><a href="/docs/exam/webpack-inter-qu.html" class="sidebar-link">关于 webpack 的面试题总结</a></li></ul></section></li><li><section class="sidebar-group depth-0"><p class="sidebar-heading"><span>文摘</span> <!----></p> <ul class="sidebar-links sidebar-group-items"><li><a href="/docs/exam/need-happy.html" class="sidebar-link">一个人需要多少土地</a></li></ul></section></li></ul> </div></div><div class="el-scrollbar__bar is-horizontal"><div class="el-scrollbar__thumb" style="width:0;transform:translateX(0%);ms-transform:translateX(0%);webkit-transform:translateX(0%);"></div></div><div class="el-scrollbar__bar is-vertical"><div class="el-scrollbar__thumb" style="height:0;transform:translateY(0%);ms-transform:translateY(0%);webkit-transform:translateY(0%);"></div></div></div></aside> <main class="page"> <div class="re-page-top"><h1 class="title"><span>开放性题目</span></h1> <div class="re-page-index"><div class="page-index-title"><span class="open-catalog"><svg aria-hidden="true" class="icon arrow-right"><use xlink:href="#icon-bold-right"></use></svg> <span class="text">目录</span></span></div> <div class="page-index-content"><div class="page-catalog" style="display:none;"><div class="synopsis-wrap"><ul class="synopsis-ul"><li class="synopsis-li"><a href="/docs/exam/actual-interview.html#mixin" class="synopsis-link">Mixin</a></li><li class="synopsis-li"><a href="/docs/exam/actual-interview.html#柯里化" class="synopsis-link">柯里化</a></li><li class="synopsis-li"><a href="/docs/exam/actual-interview.html#高阶函数" class="synopsis-link">高阶函数</a></li><li class="synopsis-li"><a href="/docs/exam/actual-interview.html#lazyman-面试题" class="synopsis-link">LazyMan 面试题</a></li><li class="synopsis-li"><a href="/docs/exam/actual-interview.html#quine" class="synopsis-link">Quine</a><ul class="synopsis-ul"><li class="synopsis-li"><a href="/docs/exam/actual-interview.html#使用正则-node-js" class="synopsis-link">使用正则（Node.js）</a></li><li class="synopsis-li"><a href="/docs/exam/actual-interview.html#使用-tostring-的特性" class="synopsis-link">使用 toString 的特性</a></li></ul></li><li class="synopsis-li"><a href="/docs/exam/actual-interview.html#使用函数实现循环" class="synopsis-link">使用函数实现循环</a></li></ul></div></div></div></div></div> <div class="theme-default-content content__default"><h1 id="开放性题目"><a href="#开放性题目" class="header-anchor">#</a> 开放性题目</h1> <h2 id="mixin"><a href="#mixin" class="header-anchor">#</a> Mixin</h2> <div class="language-js extra-class"><pre class="language-js"><code><span class="token comment">// 使用 for in 遍历</span>
<span class="token keyword">const</span> <span class="token function-variable function">mixin</span> <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token parameter">a<span class="token punctuation">,</span> b</span><span class="token punctuation">)</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
  <span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">let</span> key <span class="token keyword">in</span> b<span class="token punctuation">)</span> <span class="token punctuation">{</span>
    a<span class="token punctuation">[</span>key<span class="token punctuation">]</span> <span class="token operator">=</span> b<span class="token punctuation">[</span>key<span class="token punctuation">]</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

<span class="token comment">// 使用 Object.assign</span>
<span class="token keyword">const</span> target <span class="token operator">=</span> <span class="token punctuation">{</span> a<span class="token operator">:</span> <span class="token number">1</span><span class="token punctuation">,</span> b<span class="token operator">:</span> <span class="token number">2</span> <span class="token punctuation">}</span><span class="token punctuation">;</span>
<span class="token keyword">const</span> source <span class="token operator">=</span> <span class="token punctuation">{</span> b<span class="token operator">:</span> <span class="token number">4</span><span class="token punctuation">,</span> c<span class="token operator">:</span> <span class="token number">5</span> <span class="token punctuation">}</span><span class="token punctuation">;</span>
Object<span class="token punctuation">.</span><span class="token function">assign</span><span class="token punctuation">(</span>target<span class="token punctuation">,</span> source<span class="token punctuation">)</span>
</code></pre></div><h2 id="柯里化"><a href="#柯里化" class="header-anchor">#</a> 柯里化</h2> <p>下面的过程就是柯里化（一个函数返回一个函数）</p> <div class="language-js extra-class"><pre class="language-js"><code><span class="token keyword">const</span> <span class="token function-variable function">add</span> <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token parameter">x<span class="token punctuation">,</span> y</span><span class="token punctuation">)</span> <span class="token operator">=&gt;</span> x <span class="token operator">+</span> <span class="token number">2</span> <span class="token operator">*</span> y
<span class="token function">add</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">,</span> <span class="token number">2</span><span class="token punctuation">)</span> <span class="token comment">// 5</span>

<span class="token comment">// 这里的 fn 叫「偏函数」</span>
<span class="token keyword">const</span> <span class="token function-variable function">fn</span> <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token parameter">y</span><span class="token punctuation">)</span> <span class="token operator">=&gt;</span> <span class="token function">add</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">,</span> y<span class="token punctuation">)</span>
<span class="token function">fn</span><span class="token punctuation">(</span><span class="token number">2</span><span class="token punctuation">)</span>     <span class="token comment">// 5</span>
</code></pre></div><blockquote><p>推荐一个函数库：<a href="https://underscorejs.org/" target="_blank" rel="noopener noreferrer">Underscore.js<span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></a>，查找它的 <code>partial</code> 方法，该方法可以将一个函数柯里化。</p></blockquote> <h2 id="高阶函数"><a href="#高阶函数" class="header-anchor">#</a> 高阶函数</h2> <p>只要满足以下条件之一，就是高阶函数</p> <ul><li>接受一个或多个函数作为输入</li> <li>输出一个函数</li></ul> <p>JavaScript 中典型的内置高阶函数：<code>Function.prototype.bind()</code></p> <h2 id="lazyman-面试题"><a href="#lazyman-面试题" class="header-anchor">#</a> LazyMan 面试题</h2> <p>实现 LazyMan，能按以下方式调用</p> <ol><li>打印出一个 log</li></ol> <div class="language-js extra-class"><pre class="language-js"><code><span class="token function">LazyMan</span><span class="token punctuation">(</span><span class="token string">&quot;Hank&quot;</span><span class="token punctuation">)</span>

你好，我是 Hank
</code></pre></div><ol start="2"><li>可以链式调用</li></ol> <div class="language-js extra-class"><pre class="language-js"><code><span class="token function">LazyMan</span><span class="token punctuation">(</span><span class="token string">&quot;Hank&quot;</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">eat</span><span class="token punctuation">(</span><span class="token string">&quot;lunch&quot;</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">eat</span><span class="token punctuation">(</span><span class="token string">&quot;supper&quot;</span><span class="token punctuation">)</span>

你好，我是 Hank
吃午餐
吃晚餐
</code></pre></div><ol start="3"><li>可以指定时间后执行后续的内容</li></ol> <div class="language-js extra-class"><pre class="language-js"><code><span class="token function">LazyMan</span><span class="token punctuation">(</span><span class="token string">&quot;Hank&quot;</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">sleep</span><span class="token punctuation">(</span><span class="token number">10</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">eat</span><span class="token punctuation">(</span><span class="token string">&quot;lunch&quot;</span><span class="token punctuation">)</span>

你好，我是 Hank
（沉默十秒）
我醒了，我刚睡了 <span class="token number">10</span> 秒
吃午餐
</code></pre></div><ol start="4"><li>可以根据后面链式调用的方法控制代码最开始执行的时间</li></ol> <div class="language-js extra-class"><pre class="language-js"><code><span class="token function">LazyMan</span><span class="token punctuation">(</span><span class="token string">&quot;Hank&quot;</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">sleepFirst</span><span class="token punctuation">(</span><span class="token number">5</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">eat</span><span class="token punctuation">(</span><span class="token string">&quot;supper&quot;</span><span class="token punctuation">)</span>

（沉默五秒）
我醒了，我刚睡了 <span class="token number">5</span> 秒
你好，我是 Hank
吃晚餐
</code></pre></div><p><strong>答案</strong></p> <hr> <p>实现前两个功能</p> <div class="language-js extra-class"><pre class="language-js"><code><span class="token keyword">function</span> <span class="token function">LazyMan</span><span class="token punctuation">(</span><span class="token parameter">name</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
  console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span><span class="token template-string"><span class="token template-punctuation string">`</span><span class="token string">你好！我是 </span><span class="token interpolation"><span class="token interpolation-punctuation punctuation">${</span>name<span class="token interpolation-punctuation punctuation">}</span></span><span class="token template-punctuation string">`</span></span><span class="token punctuation">)</span>
  <span class="token keyword">const</span> api <span class="token operator">=</span> <span class="token punctuation">{</span>
    <span class="token function">eat</span><span class="token punctuation">(</span><span class="token parameter">type</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
      <span class="token keyword">const</span> hash <span class="token operator">=</span> <span class="token punctuation">{</span>
        <span class="token string">'lunch'</span><span class="token operator">:</span> <span class="token string">'吃午餐'</span><span class="token punctuation">,</span>
        <span class="token string">'supper'</span><span class="token operator">:</span> <span class="token string">'吃晚餐'</span>
      <span class="token punctuation">}</span>
      console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span>hash<span class="token punctuation">[</span>type<span class="token punctuation">]</span><span class="token punctuation">)</span>
      <span class="token keyword">return</span> api
    <span class="token punctuation">}</span>
  <span class="token punctuation">}</span>
  <span class="token keyword">return</span> api
<span class="token punctuation">}</span>

<span class="token function">LazyMan</span><span class="token punctuation">(</span><span class="token string">'小明'</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">eat</span><span class="token punctuation">(</span><span class="token string">'lunch'</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">eat</span><span class="token punctuation">(</span><span class="token string">'supper'</span><span class="token punctuation">)</span>

你好！我是小明
吃午餐
吃晚餐
</code></pre></div><p>实现第3题</p> <div class="language-js extra-class"><pre class="language-js"><code><span class="token keyword">function</span> <span class="token function">LazyMan</span><span class="token punctuation">(</span><span class="token parameter">name</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
  console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span><span class="token template-string"><span class="token template-punctuation string">`</span><span class="token string">你好！我是 </span><span class="token interpolation"><span class="token interpolation-punctuation punctuation">${</span>name<span class="token interpolation-punctuation punctuation">}</span></span><span class="token template-punctuation string">`</span></span><span class="token punctuation">)</span>
  <span class="token keyword">const</span> api <span class="token operator">=</span> <span class="token punctuation">{</span>
    <span class="token function">sleep</span><span class="token punctuation">(</span><span class="token parameter">n</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
      <span class="token keyword">const</span> time <span class="token operator">=</span> Date<span class="token punctuation">.</span><span class="token function">now</span><span class="token punctuation">(</span><span class="token punctuation">)</span>
      <span class="token keyword">while</span><span class="token punctuation">(</span>Date<span class="token punctuation">.</span><span class="token function">now</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">-</span> time <span class="token operator">&lt;</span> n<span class="token operator">*</span><span class="token number">1000</span><span class="token punctuation">)</span><span class="token punctuation">{</span><span class="token punctuation">}</span>
      console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span><span class="token template-string"><span class="token template-punctuation string">`</span><span class="token string">我醒了，我刚睡了</span><span class="token interpolation"><span class="token interpolation-punctuation punctuation">${</span>n<span class="token interpolation-punctuation punctuation">}</span></span><span class="token string">秒</span><span class="token template-punctuation string">`</span></span><span class="token punctuation">)</span>
      <span class="token keyword">return</span> api
    <span class="token punctuation">}</span><span class="token punctuation">,</span>
    <span class="token function">eat</span><span class="token punctuation">(</span><span class="token parameter">type</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
      <span class="token keyword">const</span> hash <span class="token operator">=</span> <span class="token punctuation">{</span>
        <span class="token string">'lunch'</span><span class="token operator">:</span> <span class="token string">'吃午餐'</span><span class="token punctuation">,</span>
        <span class="token string">'supper'</span><span class="token operator">:</span> <span class="token string">'吃晚餐'</span>
      <span class="token punctuation">}</span>
      console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span>hash<span class="token punctuation">[</span>type<span class="token punctuation">]</span><span class="token punctuation">)</span>
      <span class="token keyword">return</span> api
    <span class="token punctuation">}</span>
  <span class="token punctuation">}</span>
  <span class="token keyword">return</span> api
<span class="token punctuation">}</span>

<span class="token function">LazyMan</span><span class="token punctuation">(</span><span class="token string">'小明'</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">sleep</span><span class="token punctuation">(</span><span class="token number">10</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">eat</span><span class="token punctuation">(</span><span class="token string">'supper'</span><span class="token punctuation">)</span>
</code></pre></div><p>实现第4题</p> <div class="language-js extra-class"><pre class="language-js"><code><span class="token keyword">function</span> <span class="token function">LazyMan</span><span class="token punctuation">(</span><span class="token parameter">name</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
  <span class="token keyword">const</span> queue <span class="token operator">=</span> <span class="token punctuation">[</span><span class="token punctuation">]</span>
  <span class="token keyword">const</span> <span class="token function-variable function">task</span> <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span> console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span><span class="token template-string"><span class="token template-punctuation string">`</span><span class="token string">你好！我是 </span><span class="token interpolation"><span class="token interpolation-punctuation punctuation">${</span>name<span class="token interpolation-punctuation punctuation">}</span></span><span class="token template-punctuation string">`</span></span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">next</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">}</span>
  queue<span class="token punctuation">.</span><span class="token function">push</span><span class="token punctuation">(</span>task<span class="token punctuation">)</span>
  <span class="token keyword">const</span> <span class="token function-variable function">next</span> <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
    <span class="token keyword">const</span> first <span class="token operator">=</span> queue<span class="token punctuation">.</span><span class="token function">shift</span><span class="token punctuation">(</span><span class="token punctuation">)</span>
    first <span class="token operator">&amp;&amp;</span> <span class="token function">first</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token comment">// first?.()</span>
  <span class="token punctuation">}</span>
  <span class="token keyword">const</span> api <span class="token operator">=</span> <span class="token punctuation">{</span>
    _queue<span class="token operator">:</span> queue<span class="token punctuation">,</span>
    <span class="token function">sleep</span><span class="token punctuation">(</span><span class="token parameter">n</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
      <span class="token keyword">const</span> <span class="token function-variable function">task</span> <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
        <span class="token function">setTimeout</span><span class="token punctuation">(</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
          console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span><span class="token template-string"><span class="token template-punctuation string">`</span><span class="token string">我醒了，我刚睡了</span><span class="token interpolation"><span class="token interpolation-punctuation punctuation">${</span>n<span class="token interpolation-punctuation punctuation">}</span></span><span class="token string">秒</span><span class="token template-punctuation string">`</span></span><span class="token punctuation">)</span>
          <span class="token function">next</span><span class="token punctuation">(</span><span class="token punctuation">)</span> 
        <span class="token punctuation">}</span><span class="token punctuation">,</span> n<span class="token operator">*</span><span class="token number">1000</span><span class="token punctuation">)</span>
      <span class="token punctuation">}</span>
      queue<span class="token punctuation">.</span><span class="token function">push</span><span class="token punctuation">(</span>task<span class="token punctuation">)</span>
      <span class="token keyword">return</span> api
    <span class="token punctuation">}</span><span class="token punctuation">,</span>
    <span class="token function">eat</span><span class="token punctuation">(</span><span class="token parameter">type</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
      <span class="token keyword">const</span> <span class="token function-variable function">task</span> <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
        <span class="token keyword">const</span> hash <span class="token operator">=</span> <span class="token punctuation">{</span>
          <span class="token string">'lunch'</span><span class="token operator">:</span> <span class="token string">'吃午餐'</span><span class="token punctuation">,</span>
          <span class="token string">'supper'</span><span class="token operator">:</span> <span class="token string">'吃晚餐'</span>
        <span class="token punctuation">}</span>
        hash<span class="token punctuation">[</span>type<span class="token punctuation">]</span> <span class="token operator">&amp;&amp;</span> console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span>hash<span class="token punctuation">[</span>type<span class="token punctuation">]</span><span class="token punctuation">)</span>
        <span class="token function">next</span><span class="token punctuation">(</span><span class="token punctuation">)</span>
      <span class="token punctuation">}</span>
      queue<span class="token punctuation">.</span><span class="token function">push</span><span class="token punctuation">(</span>task<span class="token punctuation">)</span>
      <span class="token keyword">return</span> api
    <span class="token punctuation">}</span><span class="token punctuation">,</span>
    <span class="token function">sleepFirst</span><span class="token punctuation">(</span><span class="token parameter">n</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
      <span class="token keyword">const</span> <span class="token function-variable function">task</span> <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
        <span class="token function">setTimeout</span><span class="token punctuation">(</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
          console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span><span class="token template-string"><span class="token template-punctuation string">`</span><span class="token string">我醒了，我刚睡了</span><span class="token interpolation"><span class="token interpolation-punctuation punctuation">${</span>n<span class="token interpolation-punctuation punctuation">}</span></span><span class="token string">秒</span><span class="token template-punctuation string">`</span></span><span class="token punctuation">)</span>
          <span class="token function">next</span><span class="token punctuation">(</span><span class="token punctuation">)</span> 
        <span class="token punctuation">}</span><span class="token punctuation">,</span> n<span class="token operator">*</span><span class="token number">1000</span><span class="token punctuation">)</span>
      <span class="token punctuation">}</span>
      queue<span class="token punctuation">.</span><span class="token function">unshift</span><span class="token punctuation">(</span>task<span class="token punctuation">)</span>
      <span class="token keyword">return</span> api
    <span class="token punctuation">}</span>
  <span class="token punctuation">}</span>
  <span class="token function">setTimeout</span><span class="token punctuation">(</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span> <span class="token function">next</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">}</span><span class="token punctuation">)</span>
  <span class="token keyword">return</span> api
<span class="token punctuation">}</span>

<span class="token function">LazyMan</span><span class="token punctuation">(</span><span class="token string">&quot;小明&quot;</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">sleepFirst</span><span class="token punctuation">(</span><span class="token number">5</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">eat</span><span class="token punctuation">(</span><span class="token string">&quot;supper&quot;</span><span class="token punctuation">)</span>
</code></pre></div><blockquote><p>其中的 <code>_queue</code> 只是为了知道当前任务队列的任务，可不写。</p></blockquote> <h2 id="quine"><a href="#quine" class="header-anchor">#</a> Quine</h2> <p>请写出一个程序，它能打印自身</p> <h3 id="使用正则-node-js"><a href="#使用正则-node-js" class="header-anchor">#</a> 使用正则（Node.js）</h3> <div class="language-js extra-class"><pre class="language-js"><code><span class="token keyword">var</span> data <span class="token operator">=</span> <span class="token string">&quot;module.exports = function () { console.log(\&quot;var data = \\\&quot;%s\\\&quot;\\n%s\&quot;, data.replace(/\\\\/g, \&quot;\\\\\\\\\&quot;).replace(/\&quot;/g, \&quot;\\\\\\\&quot;\&quot;), data.replace(/{/, \&quot;{\\n   \&quot;).replace(/}$/, \&quot;\\n}\&quot;)); }&quot;</span>
module<span class="token punctuation">.</span><span class="token function-variable function">exports</span> <span class="token operator">=</span> <span class="token keyword">function</span> <span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span><span class="token string">&quot;var data = \&quot;%s\&quot;\n%s&quot;</span><span class="token punctuation">,</span> data<span class="token punctuation">.</span><span class="token function">replace</span><span class="token punctuation">(</span><span class="token regex"><span class="token regex-delimiter">/</span><span class="token regex-source language-regex"><span class="token special-escape escape">\\</span></span><span class="token regex-delimiter">/</span><span class="token regex-flags">g</span></span><span class="token punctuation">,</span> <span class="token string">&quot;\\\\&quot;</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">replace</span><span class="token punctuation">(</span><span class="token regex"><span class="token regex-delimiter">/</span><span class="token regex-source language-regex">&quot;</span><span class="token regex-delimiter">/</span><span class="token regex-flags">g</span></span><span class="token punctuation">,</span> <span class="token string">&quot;\\\&quot;&quot;</span><span class="token punctuation">)</span><span class="token punctuation">,</span> data<span class="token punctuation">.</span><span class="token function">replace</span><span class="token punctuation">(</span><span class="token regex"><span class="token regex-delimiter">/</span><span class="token regex-source language-regex">{</span><span class="token regex-delimiter">/</span></span><span class="token punctuation">,</span> <span class="token string">&quot;{\n   &quot;</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">replace</span><span class="token punctuation">(</span><span class="token regex"><span class="token regex-delimiter">/</span><span class="token regex-source language-regex">}<span class="token anchor function">$</span></span><span class="token regex-delimiter">/</span></span><span class="token punctuation">,</span> <span class="token string">&quot;\n}&quot;</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
</code></pre></div><p>调用</p> <div class="language-js extra-class"><pre class="language-js"><code><span class="token operator">&gt;</span> <span class="token function">require</span><span class="token punctuation">(</span><span class="token string">'./index.js'</span><span class="token punctuation">)</span><span class="token punctuation">(</span><span class="token punctuation">)</span>
</code></pre></div><h3 id="使用-tostring-的特性"><a href="#使用-tostring-的特性" class="header-anchor">#</a> 使用 toString 的特性</h3> <div class="language-js extra-class"><pre class="language-js"><code><span class="token keyword">function</span> <span class="token function">quine</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span>quine<span class="token punctuation">.</span><span class="token function">toString</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">}</span>
</code></pre></div><blockquote><p>参考文章：<a href="https://catonmat.net/quine-in-node" target="_blank" rel="noopener noreferrer">https://catonmat.net/quine-in-node<span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></a></p></blockquote> <h2 id="使用函数实现循环"><a href="#使用函数实现循环" class="header-anchor">#</a> 使用函数实现循环</h2> <p>实现一个数组，数组内值按照顺序每次都加 3，并且可以指定数组长度。</p> <ol><li>范围和初始值都使用参数控制。</li> <li>每次+3。</li></ol> <p>代码</p> <div class="language-js extra-class"><pre class="language-js"><code><span class="token keyword">function</span> <span class="token function">addArray</span><span class="token punctuation">(</span><span class="token parameter">number<span class="token punctuation">,</span> max</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
  <span class="token keyword">let</span> array <span class="token operator">=</span> <span class="token punctuation">[</span><span class="token punctuation">]</span>
  <span class="token keyword">function</span> <span class="token function">fn</span><span class="token punctuation">(</span><span class="token parameter">number<span class="token punctuation">,</span> max</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">if</span> <span class="token punctuation">(</span>max <span class="token operator">&lt;</span> array<span class="token punctuation">.</span>length <span class="token operator">+</span> <span class="token number">1</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
      <span class="token keyword">return</span>
    <span class="token punctuation">}</span>
    number <span class="token operator">+=</span> <span class="token number">3</span>
    array<span class="token punctuation">.</span><span class="token function">push</span><span class="token punctuation">(</span>number<span class="token punctuation">)</span>
    <span class="token keyword">return</span> <span class="token function">fn</span><span class="token punctuation">(</span>number<span class="token punctuation">,</span> max<span class="token punctuation">)</span>
  <span class="token punctuation">}</span>
  <span class="token function">fn</span><span class="token punctuation">(</span>number<span class="token punctuation">,</span> max<span class="token punctuation">)</span>
  <span class="token keyword">return</span> array
<span class="token punctuation">}</span>
console<span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span><span class="token function">addArray</span><span class="token punctuation">(</span><span class="token number">0</span><span class="token punctuation">,</span> <span class="token number">10</span><span class="token punctuation">)</span><span class="token punctuation">)</span>
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